The invention relates to a method and apparatus for filleting fishes by cutting into the fishes whilst they are conveyed with the belly facing downwards and with the tail leading. In methods of this kind, for example as described in published Norwegian Patent 3852/68, the lower half of the tail fin, and a strip of bone structure that contains the belly spines, is guided in a vertically adjustable rectilinear path while a continuous guide rail, or individual guide flaps disposed upstream of the tools, are used for guiding the back. While the rib cuts and back cuts are made, the fishes can be conveyed solely or additionally by action on the spinal column from the belly side of the fish.
Whilst with this prior construction it is possible to obtain a high through-put rate, it is practically impossible for the fillets to be cut out neatly as far as the tail root. Moreover, correctly timed termination of the cut which cuts free the belly flaps from the ribs and the vertebral appendages, is not possible so that the yield is lower than is theoretically possible owing to the loss of meat at these two positions.
Other methods suffer from the disadvantage of requiring tail clips, sliding saddles or the like for conveying the fish. These have to circulate at fixed intervals so that the through-put rate is greatly reduced when smaller fishes are being processed.